Optical fiber ends are normally carefully preparated before they are connected to light emitting or light receiving devices. Typical measures are forming tapered fiber core end faces and subsequently applying a metal covering on adjacent parts of the fiber end. In order to keep the tapered end face free from all impurities while the metal covering is applied it is necessary to provide said end face with a protective coating. The coating should preferably be easy to apply and remove and at the same time give a sufficient protection.
According to known methods such coatings are provided by dipping the end face into an unsolidified liquid state of the coating by hand and arranging for setting or drying afterwards. These manual treatments are, however, not effective in microoptoelectronic applications when the dipping of the fiber face end has to be very limited and the liquid quite often is a transparent lacquer with an indistinct surface which is hard to locate for the operator.